HYMENOPTERA. TEREBRANTIA. ] 71 



unnecessary to the vegetarian. Now in the case before 

 us this applies only to the perfect insects, which, not- 

 withstanding that their victims are usually only larvae, 

 and sometimes stationary and even enclosed larvae (as 

 the larvae in galls), are yet often put to a shift either to 

 " catch their hare," or, having caught him, to seize the 

 lucky moment for the achievement of the one work of 

 their life. In fact, the very objection only serves to 

 point out the economy more remarkably; this, which we 

 may call the predaceous character of form, being given 

 not to the individual which is to enjoy the advantage, 

 but to that which is to secure it for him, the plan being 

 thus carried out into two generations. That this is not 

 an entirely fanciful idea may be presumed from the same 

 circumstance occurring in the next section also. A 

 very slight glance at the genera of bees (in the second 

 section) will show that the lightest forms are to be found 

 amongst those which are parasitic; whilst in the present 

 division some of the heaviest forms in the Cynips family 

 are to be found amongst the gall-makers insects with 

 vegetarian larvae. 



In these insects the head is small or of moderate 

 size. The thorax is usually large in proportion to the 

 abdomen, which, however, is often of great length. The 

 abdomen varies greatly ; in all it is attached to the 

 thorax by a small point, which is sometimes drawn out 

 into a long stalk, though in a few species (of Chalcis) 

 some care is, in observing, required to avoid the mistake 

 of supposing the abdomen to be attached as in the Saw- 

 flies. In one species it is most disproportionally small, 

 whilst in others it is very long, compressed, and 

 largest at the end ; in some it is cylindrical, in others 

 ovate or conical. 



